protoc-gen-grpc-gateway doesn't work correctly with option go_package

[favadi]

Those below options are valid and generated correctly with grpc-gen-go, but doesn't work with grpc-gateway.

• option go_package = "github.com/9bug/bug;pb";
• option go_package = "github.com/9bug/bug-1";

The error message is:

E0803 14:31:41.864791   20176 generator.go:74] 11:13: expected declaration, found 'IDENT' pb: 

I created a repo to reproduce this problem, and the build result.

[favadi]

I'm trying to support this alias feature myself.

[favadi]

I submit #277 to fix the failure in first case. It passes all the tests.

[favadi]

I also pushed fix for latter case to above PR.

[favadi]

Closing this as there is a PR to track it already.